Digital audio/video content delivery and distribution systems have undergone rapid development and deployment in recent years due, at least in part, to their ability to efficiently distribute large numbers of high-fidelity video and/or audio content and programs as well as other digital services or content over a wide geographic region. For example, in the case of satellite-based digital television and wireless digital video/audio delivery systems, little, if any, land-based infrastructure (e.g., ground stations, cable lines, etc.) is needed to provide services to subscribers on a world-wide basis. As a result, such satellite-based and other wireless systems enable digital broadcasters and audio/video content providers to develop markets for their content, programs and/or services in remote and/or underdeveloped regions of the world in a cost-effective manner.
In general, regardless of whether a digital audio/video content delivery system uses one or more satellites, cable transmission lines, ground-based wireless transmission stations, the Internet or any combination thereof, such a system enables users to receive high-fidelity video and/or audio content, as well as user-interactive features or tools such as, for example, pictographic program guides, grid-based guides, etc. that enable users to plan and perform program consumption activities. More specifically, digital audio/video content delivery systems that deliver digital television may transmit one or more high-bandwidth signals, each of which is typically composed of a stream of data or data packets having a plurality of video, audio and/or other digital programs multiplexed therein. Users or subscribers typically have a digital decoder unit which, in the case of a digital video or television system, is commonly referred to as a “set-top box.” The set-top box can, based on subscriber commands, selectively de-multiplex data packets associated with a particular program from a particular data stream, decode those data packets and send a signal to a television or video monitor for viewing. Some digital televisions provide integrated or built-in set-top box functionality and, thus, do not require a separate set-top box.
Of course, as is the case with analog content providers and broadcasters, digital content providers and broadcasters (e.g., digital television, audio, etc.) desire to meter (i.e., monitor) the consumption of the programs and/or other services provided to users or subscribers to thereby generate audience program consumption behavior or patterns. Such audience consumption behavior or patterns may be used to develop program ratings information, to improve targeted marketing or advertising campaigns, to improve the types of programs and/or services and the times at which those programs and/or services are delivered, to assess the value of a particular time slot and program for purposes of determining what advertisers should pay for usage of that time slot., etc.
A metering system designed for use with an analog content delivery system, such as an analog television system, generates viewing records or other viewing information that is typically collected from a group of statistically selected households. Each of the statistically selected households has a data logging and processing unit commonly referred to as a “home unit” or “site unit.” The site unit is usually coupled to a variety of attachments that provide inputs to the site unit or that receive outputs from the site unit. For example, a frequency detector may be used to detect the local oscillator frequency of the television to identify the channel to which the television is currently tuned. Also, for example, a people counter, may be located in the viewing space of the television and in communication with the site unit, thereby enabling the site unit to actively or passively detect the identities of the persons currently viewing programs displayed on the television. In some cases, the metering system is designed to capture signature information associated with audio and/or video content that has been consumed in the household.
The site unit usually processes its inputs, including the inputs from its attachments, to produce viewing records. In general, the viewing records typically contain program identification information (i.e., information that can be used to identify a particular program, such as channel information obtained from the frequency detector and signature information) and audience information such as the numbers and/or identities of people viewing that particular program obtained from the people counter. The viewing records may be generated on a periodic basis (i.e., at fixed time intervals) or may be generated in response to a change in an input such as, for example, a change in the identities or number of persons viewing the television, a change in the channel tuning information (i.e., a channel change), etc. Of course, viewing records may contain any other information such as the identities of viewers present at the viewing time.
Often, the site unit collects a quantity of viewing records and transmits collected viewing records, usually daily, to a central office or data processing facility for further processing or analysis. The data processing facility receives viewing records from site units located in some or all of the statistically selected households and additionally receives information from one or more reference sites. The reference sites are typically configured to capture information associated with the audio/video content broadcast to specific content distribution areas. For example, a reference site may collect signatures for all of the audio and/or video content distributed within its assigned area and then transmit the collected signatures to the data processing facility. The data processing facility analyzes the viewing records to ascertain the viewing behaviors of a particular household or group of households selected from all participating households. Additionally, the central data processing facility may generate viewing behavior statistics and other parameters indicative of viewing behavior associated with all of the participating households.
To generate viewing behavior information from viewing records, the central office or data processing facility may compare each of the signatures generated by a household unit to the signatures generated by the reference site. When a signature from the household unit matches a signature from a reference site, the identity of the content associated with matching signatures may be determined using data such as a list of content (i.e., a schedule lineup of television programming or television guide) associated with the reference site signatures and/or the time at which, and the channel from which, the signature was captured at the reference site. Such a matching process may be carried out for each of the viewing records received by the data processing facility, thereby enabling the data processing facility to reconstruct what programs were watched by all participating households and the times at which the programs were watched. Alternatively, such a matching process may be used only when other data, such as channel data or time data, is unavailable.
Signature information may be used in the foregoing manner to perform content identification because each signature is designed to uniquely correspond to the content from which it was collected. Thus, a match between two signatures indicates that the matching signatures were derived from the same content. While a variety of signature generation and capture techniques are well known in the art, such techniques are suited for use with audio/video content in an analog format.